Steam actuated valve



(No Model.) 7 4 Sheets-Sheet 1.

G. E. DOW.

STEAM AGTUATED VALVE. No. 309,610. Patented Dec. '23. 1884.

(No Model.) 4 Sheets-Sheet 2.

G..E. DOW.

STEAM AGTUATED VALVE.-

No. 309.610. Patented Dec. 23, 1884.

(No Model.) 4 Sheets-Sheet 3.

G. E. 110W.v

STEAM AGTUATED VALVE. No. 309,610. Patented Dec. 23, 1884.

-N. PETERS. P mwumogrn mr, Washington, D. c

(No Model.)

4 SheetsSheet 4.

G. E. 110w. STEAM AUTUATED VALVE.

Patented Dec. 23, 1884.

Ihvrrnn dramas .a'rnsrr rricnl GEORGE E. DOW, OF SAN FRANCISCO,CALIFORNIA.

STEAM-ACTUATED VALVE.

SPECIFICATION forming part of Letters Patent No. 309,610, dated December23, 1884.

Application filed December 14,1853.

To all whom it 77mg concern.-

Be it known that I, GEORGEE. Dow, of the city and county o'fSanFrancisco, and State of California, have invented an Improvement inSteam-Actuated Valves. for Direct Acting Steam-Engines; and I herebydeclare the following to be a full, clear, and exact descriptionthereof.

My invention relates to certain improvements in direct-actingsteam-engines.

It consists of a main cylinder with a piston reciprocating therein,apiston-rod connecting the piston with the exterior apparatus to bemoved thereby, a combination of main and auxiliary valves andcorresponding ports, and an auxiliary piston by which both valves aremoved, the stem of said valve being connected by a mechanism outside ofthe cylinders with the main piston-rod, so that a positive motion isimparted to the valves, and a bracl et and guide for the sliding sleeve,through which motion is communicated to the supplemental or steam-chestpiston, with its main and auxiliary valves, from the main piston rod,together with certain details of construc tion, which will be more fullyexplained by reference to the accompanying drawings, in which- Figure 1is a longitudinal vertical section of my engine through a m, Fig. 3.Fig. 2 is an enlarged vertical section of the valve-chainber,supplemental piston, main and auxiliary valves, and steam-ports. 3 is atrans verse section taken through 3/ y, Figs. 1 and 2. Fig. I is atransverse section through 2 .2, Fig. 1. Fig. 5 is a plan of thevalve-faces, showing the ports. Fig. (i is abottom view of the anxiliaryvalve in perspective. Fig. 7 is atop view of same in perspective.

This invention is more particularly applicable to an engine for whichLetters Patent were issued to me January 10, 1882, and nam bered252,084. In this patent I have stated that any mechanism may be employedfor operating the valves which will give a positive connection with themain piston or rod to impart motion in the proper direction and ad mitof the valves completing the latter half of the stroke by steam-pressureindependent of the movement of the main piston, and I have (No model.)

shown a mechanism by which this may be accomplished.

In my present invention I have shown another mechanism for accomplishingthe same result, with certain improvements which I will proceed todescribe.

A is the main cylinder of my engine. 13 is the piston, and G is thepiston-rod, which passes through a stuiiingbox, D, in one cylinder-head,and niay pass through another stuffingbox in a pump-cylinder headconnecting with the pump-piston, so as to drive it directly when theengine is used in connection with a pump.

E is the steanrchest and valve-chamber, within which the main andauxiliary Valves F and G are moved over their respective ports.

H is the supplemental or auxiliary piston, [he ends of which fit andmove in cylindrical chambers, and the central portion is recessed toreceive the valves, the ends of the recess acting to move the valveswhen they come in contact with them while moving in either direction, asshown in my former patent. In the present casethe auxiliary valve G ismade of such a length that its ends never uncover the steam-passages Il, which lead to the ends of the sup oilemental pistonchambers; but ithas ports J J made vertically through it, through which steam isadmitted to the passages while said ports are passing over them. As theauxiliary valve fits closely the recess in the supplemental piston bywhich it is driven, it is moved the full length of the stroke of thelatter,while the main valve, being shorter, is not moved until after theauxiliary valve port J has commenced to open, as shown in my formerpatent. When this port does open, steam is admitted to the chamberbehind the supplemental piston to complete its stroke and fully open themain valve. It also carries the auxiliary valve over so far that theport J is carried beyond the passage I, and it is again closed so thatno more steam will be admitted. The passages I Iarc so located wherethey open into thesupplemental cylinders that they ofi'er suiiicientcushion on the eXhaust-steanr to prevent their striking thecylinder-heads, as shown in my former patent.

The effect of my improved valve is to cut OH the steam from the actingside of the supplemental piston when the valves have moved far enough tofully open the main ports. This makes the exhaust-cushion still moreeffective than before, as the steam is cut off from acting upon theopposite end of the supplemental piston.

K is the stem or rod of the supplemental piston which drives the valves.This rod extends out through a stuffing-box above 'and parallel with themain piston-rod, and has a sleeve, L, fitted to slide loosely upon it. Abracket, M,.is bolted to or formed with the head of the supplementalcylinder, and its outer end is bored out large enough to allow thesleeve to slide within it as aguide, thus giving a proper alignmentofthe moving ports and a steadiness to the movements, which isimportant.

N N are links, the'upper ends of which are connected by pins with theopposite sides of the sleeve, and O O are short links extending from thesides of the bracket to the links N, to which they arepivoted ashortdistance below the pins which join them to the sleeve, and they act asfulcrums about which the links N move. The lower ends of the links N areconnected by links P with a block or collar, Q, which is fixed to themain piston-rod.

The supplemental piston rod K is made of larger diameter outside thecylinder, and where it passes through the sleeve L, and has screwthreadsout upon this enlarged portion to receive the nuts S,which are thusadjusted to or from the sleeve L. The stroke of the main piston is thusregulated so that it works at all times as closely as practicable to thecylinderheads. The space between these nuts and the ends of the sleeveis suificient, so that after the valve has been started by the action ofthe lever-links N the supplemental piston will be moved the remainder ofthe distance of its stroke by steam admitted through the passage Iindependent ofthe movement of the main piston-rod or of theconnecting-levers. The links 0 and I? allow the links N to describe anarc of a circle while following the reciprocating movement of the mainpiston without affecting the direct reciprocation of the sleeve L.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a direct-acting engine, the combination of the main andauxiliaryvalve-rod with a sleeve sliding thereon between adjustablestops, a bracket forming a guide and support for the sleeve and rod, andthe link connect ing the sleet e to the main piston-rod, whereby theauxiliary valve is positively operated by the engine, and the main valveby steam, substantially as herein set forth.

2. In a direct-acting engine, the combination of an auxiliary valve anda main valve, placed side by side and driven by a supplemental piston,with a piston-rod extending through the cylinder-head and connected bylinks with the main piston-rod, adjustable nuts fitted to thesupplemental piston-rod,abracket, and a sleeve sliding upon the rodbetween the nuts and in the brackets, substantiallyas and for thepurpose herein set forth.

3. In a direct-acting engine, the combination of a supplemental pistonfor actuating both main and auxiliary valves, having a piston-rodextending outside the cylinder parallel with the main piston-rod, withtwo adjustable collars thereon, a sleeve sliding loosely upon said rodbetween the collars and moving within a bracket secured to thesupplemental cylinder, and the parallel arms pivoted upon each side ofthe sleeve and connected with the' guide by fulcrum-links, the oppositeends of the arms being connected with a collar upon the main piston-rodby links, all constructed to operate substantially as herein set forth.

4:. In a direct-acting engine, a main and auxiliary valve moving side byside upon a stationary valve-seat, a supplemental piston centrallyrecessedto receive and drive both main and auxiliary valves, andsteam-pas- 9o sages leading from the auxiliary valve-seat and openinginto the supplemental cylinder near the ends, said auxiliary valve beingof sucha length that its ends will not uncover the steam passages, andhaving ports made through its 9 5 ends corresponding with said passages,substantially as herein described.

5. In a direct-acting engine, a main and an auxiliary valve placed sideby side upon the stationaryseat, having ports, as shown, and ICO anauxiliary piston recessed or constructed to drive both valves, the mainvalve being shorter than the auxiliary valve and having lost motion,said auxiliary valve having ports made through its ends so as to openand close the I05 steam-passages at both ends of the stroke,substantially as herein described.

In witness whereof I have hereunto set my hand. 1

GEO. E. DOW.

\Vitnessesz" O. D. COLE, J. H. BLooD.

